JP5437406B2 - Method and apparatus for handoff between a source access system and a target access system - Google Patents

Description

Claiming priority under 35 USC § 119

  This application was filed on July 18, 2007 and claims the benefit of US provisional patent application serial number 60 / 950,583 entitled “UMB to Handoff”, filed March 12, 2008, US Patent Application Serial No. 12 / 047,234 entitled “Method and Apparatus for Handoff Between Access Systems”, further filed on March 16, 2007, Alleged benefit of US Provisional Patent Application Serial No. 60 / 895,365 entitled “Connection”, all assigned to the assignee of the present invention and expressly incorporated herein by reference.

Field

  The following description relates generally to wireless communications, and more particularly to methods and apparatus for session handoff procedures in heterogeneous networks.

background

  Wireless networking systems have become a widespread means of communicating with people around the world. Wireless communication devices such as cellular telephones, personal digital assistants and the like are becoming smaller and more powerful to meet consumer needs and improve portability and convenience. Consumers rely on these devices and demand reliable services, coverage area expansion, additional services (eg, web browsing capabilities), and continuous reduction in size and cost of such devices It is like that.

  In particular, as wireless technology continues to evolve, the evolution of mobile services will continue to evolve into increasingly rich and more intriguing mobile and converged services. As end users demand more, higher quality multimedia content in any environment, the evolution of data technology will continue to increase the consumption of data usage. For example, over the last few years, wireless communication technology has evolved from analog-driven systems to digital systems. In general, in conventional analog systems, analog signals are relayed on the forward and reverse links and are able to transmit and receive signals while being related to the appropriate quality. Requires quantity. Since the analog signal is continuous in time and space, no status message (eg, a message indicating receipt or non-reception of data) is generated. In contrast, packet switching systems allow analog signals to be converted into data packets and transmitted over physical channels between access terminals and base stations, routers, and the like. In addition, digital data can be relayed in its natural form (eg, text, Internet data, and the like) by using a packet switched network.

  As such, digital wireless communication systems are widely deployed to provide a variety of communication services such as telephony, video, data, messaging, broadcast and the like. Such systems typically use an access network that connects multiple access terminals to a wide area network (WAN) by sharing available network resources. An access network is typically implemented with a number of access points that are distributed throughout a geographical coverage area. Further, the geographical coverage area can be divided into cells, each cell having an access point. Similarly, the cell can be further divided into sectors. However, in such system architectures, providing efficient handoffs between access systems that do not share the same communication procedures and policies has become a difficult task.

Overview

  A simplified overview is provided below to provide a basic understanding of the description. This summary is not an extensive overview and is not intended to identify key or critical elements nor to delineate the scope of such aspects. Its sole purpose is to give some concepts in a simplified form as a prelude to the more detailed description that is presented later.

  The described aspect allows for mobile handoffs between heterogeneous networks by using an intersystem handoff control component and, in addition to session handoffs between the source and target access systems, and the mutual interaction between them. Provide connection. As such, the intersystem handoff control component (e.g., to reduce interrupts during handoffs and relax the need to perform session setup during handoffs) allows for session negotiation between the AT and the target access system. As part, tunneling can be provided in advance and packets are transported by the source access system. A tunnel can be established from the AT to the target access system, and from the AT's point of view, "mobile-target access system" signaling proceeds through such a tunnel. Such tunneling may further involve establishing other tunnels to the target access system, depending on the type of tunneling involved (eg, whether tunneling occurs at the data link layer). The source access system can further specify a target access system based on the pilot report, and the AT can communicate with the target access system and establish a process for negotiation.

  In a related aspect, along with IP tunneling between the mobile and the target access system, existing mobility models can be leveraged to ensure trust and privacy, resulting in (eg, devices crossing networks and management areas). Enables secure and seamless handoff between heterogeneous networks. Exemplary handoffs between such heterogeneous access systems may include handoffs between Ultra Mobile Broadband (UMB) and High Rate Packet Data (HRPD); WiMax / HRPD; Long Term Evolution (LTE) / HRPD. Yes, the system architecture can achieve Internet Protocol (IP) mobility using client mobile IP to actively involve the mobile in preparation for handoff. Alternatively, the system can use a system that is more network controlled than the mobile itself. Such an interconnection allows a handoff to the mobile between different access systems and allows the call to continue without dropping.

  According to an associated method, a setup can be established between a source access system and a target access system in preparation for a handoff session. Such a setup may include IP address discovery for an interworking security gateway (IWSG) that ensures the security of transmitted packets. The setup may further include discovery of an IP address for the target access system radio access network (RAN) or RAN-lite. Normally, the RAN-lite is a RAN that includes only a protocol stack and does not include a radio transceiver function. It also supports core network elements and actual RAN existing RAN interfaces. After the session is pre-established with the RAN-lite, the session can be transferred to the actual RAN through the existing RAN interface (used to support handoff between technologies and between technologies). Thereby, for example, an inter-technology handoff to the target access system can be performed without requiring an upgrade to an existing real RAN (to support L3 tunnels from the AT).

  According to a further aspect, the RAN-lite is associated with a protocol (eg, contained within the mobile and / or IWSG) so that the mobile discovers the IP address and the target wireless system It is possible to establish a tunnel to pre-setup a session for. Requesting a handover over the radio can transfer a session negotiated in the RAN-lite through a well-known existing interface. Thus, from a radio access network perspective, post-handoff access can be from the same radio technology, and therefore the target radio access system does not need to be modified to support heterogeneous system radio technology handoff. . Without any physical base station actual control, the RAN-lite can function logically as any other actual RAN (eg, base station controller). Whenever a mobile establishes a tunnel with a RAN-lite, such a mobile can negotiate a session with the RAN-lite, so that the mobile can acquire a target radio technology session, and the RAN-lite can A copy of the session for the target radio technology can be stored and the mobile can still operate with the source radio technology.

  Therefore, when handing off from mobile to target radio technology over the air, the mobile can access the actual RAN of the target access system (eg, mobile access), and the target access system exists for the technology that the session should negotiate Ask the moving body whether to do it. The mobile can further provide a unicast access terminal identifier (UATI) or equivalent identifier that can be used to locate the session, the UATI from the mobile can indicate the RAN-lite, and the actual RAN can be used to obtain a session from the RAN-lite to the actual RAN. Upon taking a session, the mobile can communicate with the actual RAN in the target wireless system. It should be understood that an actual RAN may represent a base station controller that includes the actual connection to the base station.

  The intersystem handoff control component can implement tunneling between the AT and the target access system and can transfer signaling / packeting associated with the target system through the source system. According to a further aspect, L3 tunneling provides functional and procedural processes related to transferring variable length data sequences between heterogeneous systems while maintaining quality of service and error control functions. Such tunneling can also be transparent to the underlying access system regardless of direction (eg, LTE to HRPD or HRPD to LTE) (eg, for IP packets, source There is no change to).

  In a related aspect, a computer readable medium is provided. A computer readable medium for detecting the IP address of the security gateway for the target access system and the source access system and establishing a secure tunnel to the security gateway and / or to any of the heterogeneous access systems Has computer-executable instructions.

  In accordance with a further aspect, a processor that executes instructions and / or includes modules related to discovering an address for a security gateway and establishing a tunnel between an AT and a source or target access system provide.

  To the accomplishment of the foregoing and related ends, certain illustrative aspects will now be described in connection with the following description and the annexed drawings. Although these aspects illustrate only some of the various ways in which the principles of the disclosed subject matter may be employed, the claimed subject matter is intended to include all such aspects and their equivalents. It has been. Other advantages and novel features will become apparent from the following detailed description when considered in conjunction with the drawings.

FIG. 1 illustrates an exemplary intersystem handoff control component that provides communication layer tunneling from a source access system to a target access system by a mobile through the source access system. FIG. 2 illustrates a specific handoff via L3 tunneling for Ultra Mobile Broadband (UMB) and High Rate Packet Data (HRPD) systems according to a further aspect. FIG. 3 illustrates an exemplary handoff via L3 tunneling for HRPD and UMB systems. FIG. 4 illustrates a related method for transferring session state from a source access system to a target access system, according to one aspect. FIG. 5 illustrates a layered configuration that provides handoff between user equipment and source / target access systems in accordance with certain aspects. FIG. 6 illustrates a call flow according to an exemplary aspect. FIG. 7 illustrates a system that can implement handoff in the L3 layer according to one aspect. FIG. 8 illustrates a particular system that facilitates data transmission to an access terminal when handoff is required at the L3 layer. FIG. 9 illustrates a system that can be implemented as part of sending data to the access terminal before and after the handoff at L3. FIG. 10 illustrates a system that can be used in connection with receiving an indication of a handoff and / or in response to transmitting data to an access terminal.

Detailed description

  Various aspects will now be described in connection with the drawings. In the following description, for purposes of explanation, numerous specific details are set forth in order to provide a thorough understanding of one or more aspects. However, it may be apparent that such aspects may be practiced without these specific details.

  The terms “component”, “module”, “system”, and the like, as used in this application, include, but are not limited to, hardware, firmware, a combination of hardware and software, software or It is intended to include computer-related entities, such as running software. For example, a component may be, but is not limited to being, a process running on a processor, a processor, an object, an executable, a thread of execution, a program, and / or a computer. By way of illustration, both an application running on a computing device and the computing device can be a component. One or more components may reside within one process and / or thread of execution, components may be localized on one computer, and / or distributed between two or more computers Good. In addition, these components can execute from various computer readable media having various data structures stored thereon. A component of data from one component that interacts with another component in a distributed system in a local system and / or data from one component that interacts with another system by signals through a network such as the Internet. May be communicated by local and / or remote processes, such as following a signal having one or more data packets.

  Further, various aspects are described herein for the terminal. The terminal can be a wired terminal or a wireless terminal. A terminal is a system, device, subscriber unit, subscriber station, mobile station, mobile, mobile device, remote station, remote terminal, access terminal, user terminal, terminal, communication device, user agent, user device, or user equipment ( UE). A wireless terminal can be a cellular phone, satellite phone, cordless phone, session initiation protocol (SIP) phone, wireless local loop (WLL) station, personal digital assistant (PDA), handheld device with wireless connectivity, computing device, or wireless modem It may be another processing device connected to the. In addition, various aspects related to base stations are described herein. A base station may be utilized for communicating with wireless terminals and may also be referred to as an access point, Node B, or some other terminology.

  Further, the term “or” is intended to mean an inclusive “or” rather than an exclusive “or”. That is, unless otherwise stated or apparent from context, the phrase “X uses A or B” is intended to mean any of the natural inclusive permutations. That is, the phrase “X uses A or B” is satisfied by any of the following examples: X uses A; X uses B; or X uses both A and B. Further, the articles “a” and “an” as used in the specification and claims are generally intended to include the “one or more” unless the context clearly dictates otherwise. Should be construed to mean directing to this form.

  The techniques described herein may be used for various wireless communication systems such as CDMA, TDMA, FDMA, OFDMA, SC-FDMA, and other systems. The terms “system” and “network” are often used interchangeably. A CDMA system may implement a radio technology such as Universal Terrestrial Radio Access (UTRA), cdma2000, and so on. UTRA includes Wideband-CDMA (W-CDMA) and other variants of CDMA. In addition, CDMA2000 covers IS-2000, IS-95 and IS-856 standards. The TDMA system may implement a radio technology such as a global system for mobile communication (GSM (registered trademark)). OFDMA systems include evolved UTRA (E-UTRA), ultra mobile broadband (UMB), IEEE 802.11 (Wi-Fi), IEEE 802.16 (WiMAX), IEEE 802.20, flash-OFDM (registration). A wireless technology such as a trademark) may be realized. UTRA and E-UTRA are part of Universal Mobile Telecommunications System (UMTS). 3GPP Long Term Evolution (LTE) is a release of UMTS that uses E-UTRA, which uses OFDMA on the downlink and SC-FDMA on the uplink. UTRA, E-UTRA, UMTS, LTE and GSM are described in documents from an organization named “3rd Generation Partnership Project” (3GPP). In addition, CDMA2000 and UMB are described in documents from an organization named “3rd Generation Partnership Project 2” (3GPP2).

  Various aspects or features are presented in connection with a system that includes a number of devices, components, modules, and the like. It should be understood and appreciated that the various systems may include additional devices, components, modules, etc. and / or may not include all devices, components, modules, etc. discussed with the drawings. A combination of these approaches may be used.

  FIG. 1 illustrates a network system 100 that provides handoff between heterogeneous networks and interconnection between a source access system 110 and a target access system 112. It should be understood that such a diagram is exemplary in nature and the intersystem handoff control component can be part of an access terminal (AT). A session between the AT and the target system can be pre-established (transparently with respect to the source system), eg, through an L3 tunnel. Such an intersystem handoff control component 115 facilitates the setup of L3 tunneling by the mobile 104, and the mobile 104 operates in dual mode (both in the source access system 110 and the target access system 112). The intersystem handoff control component 115 initially enables the mobile 104 to obtain the local domain name associated with the source access system and / or the target access system 110, 112. Thereafter, the intersystem handoff control component facilitates discovery of IP addresses for the target access system 112 security gateway and radio access network (RAN). Such a gateway acts as a network point for entry into the target access system 112. Thus, the intersystem handoff control component 115 allows the mobile 104 to establish L3 tunneling, and the signaling and packeting associated with the target access system 112 can be transferred through the source access system in a seamless manner. .

  As such, the intersystem handoff control component 115 uses the tunneling prior to handoff to exchange the handover setup and execution packets as part of the session negotiation between the AT 104 and the target access system 112. During the handoff and can ease the request to perform session setup. The inter-system handoff control component 115 further allows communication data packets to be transported through the source access system 110, where such source access system 110 is typically involved during negotiations between the AT 104 and the target access system 112. do not do.

  2 and 3 illustrate certain aspects for handoff via L3 tunneling from the UMB system 210 to the HRPD system 215 and vice versa. In FIG. 2, the source access system is represented by a UMB system 210, where an access terminal or mobile 211 communicates with an evolved base station (eBS) 222, and IP packets are sent from the eBS through the gateway and home agent to the Internet. Forwarded to When there is a request for handoff from UMB 210 (representing the source access system) to HRPD access system 215 (representing the target access system), setup for HRPD is initiated, and during setup, mobile 211 remains in UMB system 210. It stays. The inter-system handoff control component can implement tunneling between UMB 210 and HRPD 215 and can transparently forward HRPD signaling and associated packeting via UMB system 210 via L3 tunneling that may be transported over IP.

  Thus, the path line 250 represents a traffic line, and the mobile 211 in the UMB 210 is responsible for the HRPD 215's radio access network RAN / RAN lite 212 and associated IP to prepare and set up communications (eg, for packet forwarding). Requires address discovery. Upon discovery of the IP address, signaling to the HRPD 215 can be sent through such a RAN lite IP address / packeting, and the packet can pass through the access gateway (AGW) 217 in the UMB system and can be sent to the RAN light 212. A packet data serving node (PDSN) 219 acts as a connection point between the HRPD RAN 212 and the IP network, and an interworking security gate (IWSG) 214 provides security (eg, for IP) through the IPsec tunnel 260 to provide the AT 211 And secure the transmission of packets between the RAN / RAN lite 212. Such a gateway 214 acts as a network point for entry into the HRPD target access system 215. Further, the session reference network controller (SRNC) 218 generally includes a configuration associated with an authentication function that is negotiated between the base station 222 and the access terminal 211, where the base station 222 retrieves information (eg, Serves as a reference to get session information to avoid contention during session changes).

  Similarly, FIG. 3 illustrates a further aspect for handoff by L3 tunneling from HRPD 310 to UMB system 315. When a handoff request is made from the source system HRPD 310 to the target system UMB 315, the UMB RAN / lite-eBS 312 can be discovered and associated with the identified UMB gateways 316, 325. For example, first, the UMB RAN-lite 312 associated with the Interworking Security Gateway (IWSG) 325 can be discovered. Thereafter, when such an IP address is discovered, the packet can be sent to the destination IP address based on tunneling in layer 3 of the communication protocol. Such pre-setup can facilitate subsequent packet flow to the UMB target system 315.

  FIG. 4 illustrates an exemplary method for handoff between heterogeneous systems according to one aspect. Although the exemplary method is illustrated and described as a series of blocks representing various events and / or actions, the subject aspects are not limited by the order in which such blocks are described. For example, according to the described aspects, some operations or events may occur in a different order apart from the order described herein and / or may occur concurrently with other operations or events. . Further, not all described blocks, events or actions may be required to implement a method in accordance with the subject matter aspect. Moreover, exemplary methods and other methods in accordance with the described aspects are not only implemented in connection with the methods illustrated and described herein, but are also not shown or described in other systems and devices. It is understood that this may be realized in connection with Initially, at 410, a change in radio conditions can be detected, which can trigger a request for handoff preparation from the AT to the target access system. Alternatively, the trigger for handoff preparation can be attributed to the advertisement of the target access system as a neighbor technology to the source access system. Thereafter, at 412, a setup can be established between the AT and the target access system in preparation for the handoff session. Such a setup may include, at 416, IP address discovery for an interworking security gateway that ensures the security of outgoing packets. At 418, the setup may further include IP address discovery for the RAN / RAN-lite of the target access system. At 420, an intersystem handoff control component can implement tunneling between the AT and the target access system, and signaling / packeting associated with the target system can be transferred through the source system. Further, at 422, the AT negotiates a radio interface session and an IP session with the target access system. Thus, at 424, a request for radio resources from the target system is received, followed by allocation of radio resources from the target system to the AT at 426. Thus, at 430 (or can be positioned after operation 434), IP traffic can be redirected to the AT, followed by completion of the handover at 432. Thereafter, at 434, the AT acquires the target system over the air.

  The following is a specific example of a fully qualified domain name for a DNS lookup that any IP host (such as an AT) can perform by a DNS server. Exemplary calls for target system security gateway and RAN / RAN-lite discovery may include:

Active handoff from UMB to HRPD
<HRPD-subnet>. HRPD. IWSG. <Local domain name>
<HRPD-subnet>. HRPD. RAN. <Local domain name>

Active handoff from HRPD to UMB
<UMB-ANID>. UMB. IWSG. <Local domain name>
<UMB-ANID>. UMB. RAN. <Local domain name>

Active handoff from WiMAX to HRPD <HRPD-subnet>. HRPD. IWSG. <Local domain name>
<HRPD-subnet>. HRPD. RAN. <Local domain name>

Active handoff from HRPD to WiMAX <WiMAX-APID>. WiMAX. IWSG. <Local domain name>
<WiMAX-APID>. WiMAX. RAN. <Local domain name>

Active handoff from LTE to HRPD <HRPD-Subnet>. HRPD. IWSG. <Local domain name>
<HRPD-subnet>. HRPD. RAN. <Local domain name>

Active handoff from HRPD to LTE <LTE-eNBID>. LTE. IWSG. <Local domain name>
<LTE-eNBID>. LTE. RAN. <Local domain name>

  The HRPD subnet, UMB ANID, WiMAX APID and LTE-eNBID can be obtained either directly over the air by the target access system or through a neighbor technology record advertised by the source access system.

  FIG. 5 illustrates an exemplary block diagram for interaction between user equipment or access terminal 510, source access system 540 and target access system 560. UE 510 includes both target system protocol 511 and source system protocol 512, allowing dual mode operation with both systems. Such a configuration allows discovery for the IP address of the IWSG and establishes an IPsec tunnel. In addition, the target RAN IP address can be discovered to enable pre-setup of the target RAN session. The configuration 500 facilitates session handoff from the source access system 540 to the target access system 560 using handover preparation and handover execution prior to handover by implementing an IPsec tunnel.

  FIG. 6 illustrates an exemplary call flow 600 for establishing an IP security tunnel, according to further aspects. The AT 602 is initially associated with the source access system 604 and obtains the domain name for the target access system through call 610. Therefore, the AT 602 issues a Domain Name System (DNS) 606 query to obtain an IP address for the Interwork Security Gateway (IWSG) 608 to access the target access system. Moreover, such a DNS query may further include discovery of an IP address for the RAN / RAN lite of the target access system. The AT 602 can initiate tunneling to the target access system and can transfer signaling / packeting associated with the target system through the source system 604. As previously described, exemplary handoffs between such heterogeneous access systems can include UMB / HRPD; WiMax / HRPD; LTE / HRPD handoffs, and the system architecture is ready for handoffs. In order to actively move or access terminal 602, client mobile IP can be used to achieve IP mobility, or alternatively, a more network-controlled system than the mobile itself can be used. Such an interconnection can allow session handoff to the mobile between different access systems and continue the call without dropping.

  FIG. 7 illustrates exemplary heterogeneous wireless communication systems 711, 712 that can provide services to the wireless terminal 726. Systems 711, 721 represent a target access system and a source access system, respectively, and include multiple sectors 702, 704, 708 and 706, 710, 712. Target access system 711 and source access system 721 may use different wireless services within such a sector. Although such sectors are shown as being essentially hexagonal and substantially similar in size, the size and shape of these sectors is the geographical area of physical obstacles such as buildings. It will be understood that it can vary depending on the number, size, shape, and several other factors. Access points (base stations, access routers, etc.) 714, 716, 720 are associated with sectors 702, 704, 708, where technology “A” is used. Similarly, access points 718, 722, 724 are associated with sectors 706, 712, 710, where technology “B” is used. Here, the technique “B” is different from the technique “A”.

  Because wireless terminal 726 moves geographically, wireless terminal 726 may receive a signal with greater strength from target access system 711 when compared to the received signal from source access system 721. It should be understood that the wireless terminal 726 can operate in dual mode with both the source access system 721 and the target access system 711, and the intersystem handoff control component 719 is responsible for one session negotiation between the AT 726 and the target access system 711. As part, tunneling can be provided prior to handoff. Thus, data packets can be transported (transparently or non-transparently) through the source access system 721 while the AT is preparing for a handoff to the target system, and then once the handoff is complete, the data packet Can be redirected to the target system.

  FIG. 8 illustrates a particular system 800 that facilitates the process of transferring data between disparate access systems when a handoff is required through L3 tunneling established by a mobile. System 800 includes a group of components 802 that can be associated with access points and that can communicate with each other regarding transmitting data to access terminals during handoffs between disparate access systems. Group 802 includes a component 804 that determines that an access terminal is requesting a handoff from a first access system to a second access system. For example, such a determination can occur by analyzing the identity of the target access system by the access terminal. Such identification can include any suitable indicia used to identify the IP address of the target system module among one or more other access system modules. It should be recognized that the various processes for identifying target access can be considered for the description aspect and are intended to be covered thereby.

  Group 802 also receives not only data from the first access, but also an indication as to what data should be transmitted to the access terminal next from the first access system. 806 included. For example, a time stamp or other sequence number in the RLP packet header can indicate what data should be sent to the access terminal next. Group 802 additionally includes a component 808 that receives data from the network module, and the data is preferably transmitted to the access terminal. Further, the data received from the network module can be an IP-encapsulated data packet associated with a sequence number or stamp so that the second transceiver function can receive any data Can then be transmitted to the access terminal. Group 802 can further include a component 810 that transmits data to the access terminals in an appropriate sequence, where the data is received from the first access system and the network module. For example, the second access system can receive data to be transmitted to the access terminal, where the data is not duplicated and is transmitted in a specific sequence. System 800 can also include a memory 812 that can retain instructions relating to executing components 804-810. Even if the source has not relinquished control and the data is lined up in the target access system, the system 800 allows the new or target access system to begin receiving data in preparation for the handoff. . Such target access systems have the information necessary to recover information about network layer protocols and transmitted data, and by not interrupting current data transfer, handoffs are substantially faster and with lower latency. Can occur. System 800 can be incorporated as part of a distributed and / or centralized architecture.

  FIG. 9 illustrates a system 900 that can be used in connection with transmitting data to an access terminal before and after a handoff at the L3 layer. The system 900 includes a receiver 902 that receives signals from one or more receive antennas and performs normal operations on the received signals (eg, filtering, amplifying, and downconverting), for example. (...) and digitize the conditioned signal to obtain a sample. A demodulator 904 can demodulate received pilot symbols and provide them to a processor 906 for channel estimation.

  The processor 906 may be a processor dedicated to analyzing information received by the receiver component 902 and / or generating information for transmission by the transmitter 914. A processor 906 analyzes the information received by the processor that controls one or more portions of the system 900 and / or the receiver 902 and generates information for transmission by the transmitter 914 to generate one or more of the systems 900. It is possible to use a processor that controls this part. System 900 can include an optimization component 908 that can optimize the performance of user equipment before, during, and / or after handoff. Optimization component 908 may be incorporated into processor 906. The optimization component 908 can include optimization code that performs utility-based analysis with respect to determining whether to handoff from the source access system to the target access system. The optimization code may utilize artificial intelligence based methods for performing inference and / or probabilistic decisions and / or statistical based decisions for performing handoffs.

  The system (user equipment) 900 can additionally comprise a memory 910, which is operatively coupled to the processor 906 and stores information such as signal strength information for the base station, scheduling information, and the like. Such information can be used for storing and determining whether to request a handoff and when to request a handoff. Memory 910 can additionally store protocols associated with generating lookup tables, etc., such that system 900 can use the stored protocols and / or algorithms to Performance can be improved. It will be appreciated that the data storage (eg, memory) component described herein can be either volatile memory or nonvolatile memory, or can include both volatile and nonvolatile memory. By way of illustration and not limitation, non-volatile memory may be read-only memory (ROM), programmable ROM (PROM), electrically programmable ROM (EPROM), electrically erasable ROM (EEPROM), or flash memory. Can be included. Volatile memory can include random access memory (RAM), which acts as external cache memory. By way of example, and not limitation, RAM can be utilized in many forms, such as synchronous RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), double speed data rate SDRAM (DDR SDRAM), enhanced SDRAM (ESDRAM). , Sync link DRAM (SLDRAM), and direct RAM bus RAM (DRRAM (registered trademark)). The memory 910 is not limited to these and is intended to comprise these and any other suitable type of memory. The processor 906 is connected to a symbol modulator 912 and a transmitter 914 that transmits the modulated signal.

  FIG. 10 illustrates a system that can be used in connection with receiving a handoff indication and / or in response to transmitting data to an access terminal. The system 1000 includes a base station 1002 having a receiver 1010 that receives signals from one or more user devices 1004 via one or more receive antennas 1006 and a plurality of transmit antennas 1008. To one or more user devices 1004. In one example, receive antenna 1006 and transmit antenna 1008 can be implemented using a single set of antennas. Receiver 1010 can receive information from receive antennas 1006 and is operatively associated with a demodulator 1012 that demodulates received information. Receiver 1010 can be, for example, a rake receiver (eg, a technique that individually processes multipath signal components using multiple baseband correlators,...), An MMSE-based receiver, or an assignment to it. Can be any other suitable receiver that separates the user devices being connected and will be understood by those skilled in the art. For example, multiple receivers can be used (eg, one for each receive antenna), and such receivers can communicate with each other to provide improved estimation of user data. The demodulated symbols are analyzed by a processor 1014 that is similar to the processor described above with respect to FIG. 9 and is coupled to a memory 1016 that stores information related to user device assignments, lookup tables related thereto, and the like. Has been. The output of the receiver for each antenna can be jointly processed by the receiver 1010 and / or the processor 1014. Modulator 1018 can multiplex a signal for transmission to user device 1004 through transmit antenna 1008 by transmitter 1020.

  As used in this application, the terms “component”, “system” and the like refer to computer-related entities, hardware, combinations of hardware and software, software or running software, and / or Alternatively, it is directed to refer to an electromechanical unit. For example, a component may be, but is not limited to being, a process running on a processor, a processor, an object, an instance, an executable, a thread of execution, a program, and / or a computer. By way of illustration, both an application running on a computer and the computer can be a component. One or more components may reside within one process and / or thread of execution, components may be localized on one computer, and / or distributed between two or more computers Good.

  The word “exemplary” is used herein to mean serving as an example, instance, or illustration. Any aspect or design described herein as “exemplary” is not necessarily to be construed as preferred or advantageous over other aspects or designs. Similarly, the examples are provided for purposes of clarity and understanding only and are not intended to limit the described aspects or portions thereof in any way. It should be understood that there are myriad additional or alternative examples, which have been omitted for the sake of brevity.

  Further, a system, method, apparatus, or control system that uses standard programming and / or engineering techniques to generate software, firmware, hardware, or any combination thereof to control a computer to implement the disclosed aspects All or some of the described aspects may be realized as a manufactured product. For example, computer readable media include magnetic storage devices (eg, hard disks, floppy disks, magnetic strips ...), optical disks (eg, compact disks (CD), digital versatile disks (DVD) ...). , Smart cards, and flash memory devices (eg, cards, sticks, key drives ...), but are not limited to these. In addition, carrier waves can be used to carry computer readable electronic data such as those used when sending and receiving e-mail or accessing a network such as the Internet or a local area network (LAN). Should be understood. Of course, those skilled in the art will recognize many modifications may be made to this configuration without departing from the scope or spirit of the claimed subject matter.

  When the systems and / or methods described herein are implemented in software, firmware, middleware or microcode, program code or code segments, they may be stored in a machine-readable medium such as a storage component. Good. A code segment may represent a procedure, function, subprogram, program, routine, subroutine, module, software package, class, or any combination of instructions, data structures, or program statements. A code segment may be coupled to another code segment or a hardware circuit by passing and / or receiving information, data, arguments, parameters, or memory contents. Any suitable means may be used to pass, transfer, or transmit information, arguments, parameters, data, etc., including memory sharing, message passing, token passing schemes, network transmissions, and the like.

  For software implementation, the techniques described herein can be implemented by modules (eg, procedures, functions, etc.) that perform the functions described herein. The software code can be stored in a memory unit and executed by a processor. The memory unit can be implemented within the processor or external to the processor, and in either case, the memory unit can be communicatively coupled to the processor by various means.

What has been described above includes examples of the disclosed subject matter. Of course, for the purpose of describing such subject matter, it is not possible to describe all possible combinations of components or methods, but those skilled in the art will recognize that many additional combinations and permutations are possible. can do. Accordingly, the subject matter is intended to embrace all such alterations, modifications and variations that fall within the spirit and scope of the appended claims. Moreover, so long as the term “comprising” is used in either the detailed description or in the claims, such terms are interpreted when the term “comprising” is used as a transition term in the claims. As such, the term “comprising” is intended to be similar in some ways and inclusive.
Hereinafter, the invention described in the scope of claims of the present application will be appended.
[1] In a method of session handoff between a source access system and a target access system,
Discovering the address of the target access system for tunneling from an access terminal (AT) communicating with the source access system;
Tunneling a secure channel to the target access system;
Forwarding user traffic from the source access system by a tunneling operation to the target access system and through the source access system.
[2] The method of [1] above, wherein the tunneling operation further comprises tunneling a secure channel to a security gateway of the target access system.
[3] The method of [1] above, further comprising providing a unicast access terminal identifier (UATI) to locate a session associated with the access terminal.
[4] The method of [3] above, further comprising indicating the RAN-lite of the target access system by the UATI to facilitate establishment of a tunnel to the RAN-lite of the target access system.
[5] The method of [1] above, further comprising monitoring a pilot of the target access system while operating in the source radio access system.
[6] further comprising establishing a tunnel from the AT to the source access system, wherein the source access system or the target access system is based on at least one of 3GPP specifications, 3GPP2 specifications or IEEE specifications The method according to [1] above, which is operable.
[7] The above [1], further comprising negotiating a session between the AT and the target access system to facilitate handover of the AT communication session from the source access system to the target access system the method of.
[8] The method according to [1], further comprising: receiving an advertisement indicating that the AT is reaching an end of coverage from the target access system; and starting the tunneling based on the reception operation. ] The method of description.
[9] The method of [2] above, further comprising pre-establishing a session with a module including a protocol for negotiating a session for the target access system.
[10] The method of the above-mentioned [10], further comprising providing the handoff to the actual RAN through an in-technology handoff interface.
[11] In at least one processor configured to provide session handoff;
A first module for discovering an address of the target access system for tunneling between the source access system and the target access system;
At least one processor comprising a second module for establishing a secure tunnel from the AT to the security gateway of the target access system through the source access system.
[12] In a computer program product,
A first set of codes for causing a computer to find the address of the security gateway of the target access system for tunneling from the access terminal;
A second set of codes for establishing a secure tunnel to a security gateway of the target access system and redirecting user traffic thereto;
A computer program product comprising a computer readable medium including:
[13] In the apparatus,
Discovery means for discovering the address of the RAN-lite associated with the target access system for tunneling from the access terminal;
Transmitting means for transmitting signals between the heterogeneous source access system and the target access system;
Means for transmitting a packet from an AT to the target access system through the transmission means.
[14] In a method of session handoff between a source access system and a target access system,
Discovering the address of the target access system for tunneling from the access terminal;
Tunneling a secure channel to a security gateway of the target access system;
Receiving user traffic by the target access system by the tunneling operation.
[15] The method of [14] above, further comprising establishing a radio access session via an IP session through the secure channel by using a UATI provided by the AT.
[16] The method of [14] above, further comprising receiving a pointer to the RAN-lite of the target access system and thereby triggering a handoff.
[17] The method of [14] above, further comprising monitoring a pilot of the target access system while operating in the source radio access system.
[18] further comprising establishing a tunnel from the AT to the target access system, wherein the source access system or the target access system is based on at least one of a 3GPP specification, a 3GPP2 specification, or an IEEE specification The method according to [14] above, which is operable.
[19] The above [14], further comprising negotiating a session between the AT and the target access system to facilitate a handover of the AT communication session from the source access system to the target access system the method of.
[20] The method of the above-mentioned [14], further comprising starting a preparatory step for handover to the target access system upon triggering a predetermined event.
[21] The method of the above-mentioned [14], further comprising sending an advertisement by the target access system.
[22] The method of the above-mentioned [14], further comprising establishing a session with the RAN-lite of the target access system in advance to facilitate communication with an actual RAN.
[23] In at least one processor configured to provide session handoff;
A first module for discovering the address of the security gateway of the target access system;
At least one processor comprising a second module for establishing a tunnel from an access terminal to the target access system by a source access system.
[24] In a computer program product,
A first set of code for causing a computer to find the address of the security gateway for the target access system;
A second set of codes for establishing by the source access system a tunnel from the access terminal to the RAN-lite of the target access system;
A computer program product comprising a computer readable medium including:
[25] In the device,
Discovery means for discovering the address of the target access system for tunneling from the access terminal;
Means for establishing a secure channel through a source access system to a security gateway of the target access system;
Transmission means for transmitting a signal through the secure channel.
[26] The communication system according to [25], further comprising means for tunneling to the access terminal in a data link layer.
[27] The communication system according to [26], further including means for identifying a RAN-lite of the target access system.
[28] The communication system according to [27], further comprising means for preparing a session handover to the target access system.

Claims (23)

In a method of session handoff between a source access system and a target access system,
Discovering the address of the target access system by an access terminal (AT) in communication with the source access system;
Using the address to tunnel a secure channel from the AT to the target access system through the source access system;
Forwarding signaling associated with the target access system from the AT to the target access system via the secure channel;
The method wherein the tunneling is configured to negotiate a radio interface session between the AT and the target access system.   The method of claim 1, wherein the tunneling further comprises tunneling a secure channel to a security gateway of the target access system.   The method of claim 1, further comprising providing a unicast access terminal identifier (UATI) to locate a session associated with the access terminal.   The method of claim 1, further comprising monitoring a pilot of the target access system while operating in the source radio access system.   Further comprising establishing a tunnel from the AT to the source access system, wherein the source access system or the target access system is operable based on at least one of 3GPP specifications, 3GPP2 specifications or IEEE specifications. The method of claim 1.   Further comprising negotiating a radio interface session between the AT and the target access system over the secure channel to facilitate handover of the AT communication session from the source access system to the target access system. The method of claim 1.   The method of claim 1, further comprising: receiving an advertisement from the target access system indicating that the AT is reaching an edge of coverage; and initiating the tunneling based on the receive operation. .   The method of claim 1, wherein forwarding the signaling includes negotiating a session in a protocol of the target access system prior to a handoff from the source access system to the target access system. At least one processor configured to perform a session handoff;
A first module for discovering an address of the target access system for tunneling between the source access system and the target access system;
Using the address to establish a secure tunnel from an access terminal (AT) to a security gateway of the target access system; and
The tunnel is configured to negotiate a radio interface session between the AT and the target access system and extends through the source access system. When executed by one processor even without low, a computer-readable storage medium storing a set of code that executes a session handoff between a source access system and the target access system to the at least one processor,
The set of codes is
A first set of codes for discovering a security gateway address of the target access system for tunneling from an access terminal;
A second set of codes for establishing a secure tunnel to the target access system security gateway using the address and redirecting user traffic to the target access system via the secure tunnel; Including
The computer readable storage medium , wherein the secure tunnel is configured to negotiate a radio interface session between the AT and the target access system. In the access terminal,
Discovery means for discovering an address of a target access system for tunneling from the access terminal;
Means for using the address to establish a secure channel to a security gateway of the target access system, the secure channel negotiating a radio interface session between the access terminal and the target access system Configured for, and
An access terminal comprising: transmission means for transmitting a signal through the secure channel. In a method of session handoff between a source access system and a target access system,
Discovering the address of the target access system for tunneling from an access terminal (AT);
Using the address to tunnel a secure channel extending from the AT to a security gateway of the target access system;
Receiving user traffic from the target access system at the AT via the secure channel;
The method wherein the tunneling is configured to negotiate a radio interface session between the access terminal and the target access system.   The method of claim 12, further comprising establishing a radio access session with an IP session over the secure channel by using a UATI provided by the AT.   The method of claim 12, further comprising monitoring a pilot of the target access system while operating in the source access system.   The method of claim 12, wherein the source access system or the target access system is operable based on at least one of a 3GPP specification, a 3GPP2 specification, or an IEEE specification.   Further comprising negotiating a radio interface session between the AT and the target access system over the secure channel to facilitate handover of the AT communication session from the source access system to the target access system. The method of claim 12.   13. The method of claim 12, further comprising initiating a handover preparation phase to the target access system upon triggering a predetermined event.   The method of claim 12, further comprising sending an advertising by the target access system. At least one processor configured to perform a session handoff;
A first module for discovering the address of the security gateway of the target access system;
Using the address of the security gateway to establish a tunnel from an access terminal to the target access system; and
The tunnel includes a secure channel extending through a source access system and is configured to negotiate a radio interface session between the access terminal and the target access system. When executed by the processor, the computer readable storage medium storing a set of code that executes a session handoff between a source access system and the target access system to the processor,
The set of codes is
A first set of codes for discovering a security gateway address for the target access system;
A second set of codes for establishing a tunnel from an access terminal to the target access system using the address of the security gateway;
The computer- readable storage medium , wherein the tunnel extends through the source access system and is configured to negotiate a radio interface session between the access terminal and the target access system. In an apparatus for session handoff between a source access system and a target access system,
Discovery means for discovering an address of the target access system for tunneling from an access terminal;
Means for tunneling a secure channel through the source access system to a security gateway of the target access system using the address of the target access system, the secure channel comprising the access terminal and the target access Means configured to negotiate a radio interface session between the systems;
Transmission means for transmitting a signal through the secure channel. Means for negotiating a radio interface session between the AT and the target access system over the secure channel to facilitate handover of the AT communication session from the source access system to the target access system; The apparatus of claim 21 comprising.   The apparatus of claim 21, further comprising means for negotiating the radio interface session in a protocol of the target access system prior to a handoff from the source access system to the target access.

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